Internal-combustion engine.



No. 733,350. PATENTED JULY 7, 1903. H. P. WALLMANN.

INTERNAL COMBUSTION ENGINE.l

APPLICATION FILED OGT.15, 1897. N0 MODEL. 2 SHEETS-SHEET 1.

TH: cams vzw-sas co. worcxlrm, WASHINGTON. uf c.

No. 733,350. .PATENTED JULY '7, 11903.. I H. E. WALLMANN. INTERNAL COMBUSTION ENGINE.

APPLICATION FILED 0GT.15, 1897. A N0 MODEL. 2 SHEETS-SHEET 2.

L T' L j 7&7 J

0,1 y 0 I I r: r l: i; L 'l l .I \I 'T A Home] UNITED STATES atented July PAIENI IEICE.

IIENNING F. WALLMANN, or CHICAGO, ILLINOIS, AssIeNon To TI-IEWALL- MANN ENGINE COMPANY, A CORPORATION or ILLINOIS.

INTERNAL-COMBUSTiON ENGINE.

SPECFCATION forming part of Letters Eatent No. 733,850, dated July '7, 1903.

Application led October 15,1897. Serial No. 655,357. (No model.)

To @ZZ wwnt t Netty concern:

Be it known th at I, HENNING FWALLMANN, a citizen ofthe United States, residing at Ghicago, in the county of Cook and State of lilinois, have invented certain new and useful Improvements in Internal-Combustion Engines, of which the following is a specification.

My invention relates to that class of enxo gines in which a combustible fuel-as gas, petroleum, coal-dust, or any other vsuitable fuel-is mixed with and burned in the presence of a body of compressed air in the combustion-cylinder of an engine, whereby said I5 body of compressed air is heated and enpanded and the expanding gases are made to perform work against the piston.

An engine of the general class referred to is shown in my former patent, No. 548,824, 2o October 29, 1895; and my present invention is in the nature of improvements upon the construction of the engine presented in my aforesaid patent, the objects of said improvements being, first, to more advantageously utilize the elasticity of the burning gases by expanding them within and through two cylinders-viz. a high-pressure combustion-cylinder and a low-pressure and low-temperature expansion-cylinder; second, to simplify 3o the mechanism of the engine by performing the low expansion and the compression of the air in one and the same cylinder, but on opposite sides of the piston; third, to store such air compressed in excess of the amount of air Consumed by the engine in a suitable reservoir in order to effect the starting of the engine without hand-power; fourth, to regulate the quantity of fuel consumed, especially of gas, by means of a separate fuel- 4o pump, Which, in connection with a pressureregulating device, supplies to the engine just the amount of fuel required; fth, to control the operation of the engine in a simple and efficient manner; sixth, to improve on the detail construction of engines of this character.

My invention is illustrated in the accompanying drawings, in which- Figure 1 is an elevation, partly in central 5o vertical section, of my improved engine. Fig. 2 is a vertical section of the engine on the line M N of Fig. l at right angles to the section of Fig. l and showing the valve mechanism controlling communication between the cylinders; and Figs. 3 and L are plan 55 views in the nature of diagrams, showing the valve-ports and the main controllingvalve in two different positions.

Similar letters of reference refer to similar parts throughout the several views.

A represents a suitable cast-iron frame supporting the combustion-cylinder U. The latter is lined with some non-porous reproof material-such as compressed mica, compressed asbestos, soapstone, porcelain, dtc.- and is provided through approximately the lower half of its interior surface with a series of metal rings Z Z, separated by non-conductors of heat from each other and from the outside shell of the cylinder.

A represents a plunger working in the cylinder U and having its inner end made out of sections separated from each other by nonconductors of heat and provided over approximately the lower half of its exterior surface with a series of metal rings Z' Z, separated by non-conductors of heat from each other and from the inner metal bodyof the piston. The two series of metal rings Z Z and Z Z form a regeneratorforapurposehereinafterdescribed. 8o The plunger A is connected to a crank h2 on the crank-shaft G by means of a connectingrod b, and its lower elongated cylindrical eX- tension works through a stuffing-box S,formed in the lower head of cylinder U.

B represents a combined low-pressure eX- pansion-cylinder and air-compressor supported by a cast-iron frame B. B2 is the piston of this cylinder, whose piston-rod b' passes through a suitable stuffing-box in the lower 9o head of the cylinder and is connected to a flywheel G on shaft G by a pitman aand crankpin a. The upper end of this cylinder is designed to receive the exhaust from the cornbustion-cylinder U, and its lower end or cyl- 95 inder-head is equipped with air inlet and discharge valves 'u and o, respectively, for the compression of air.

Supported by a suitable cast-iron frame C above the cylinder B and in vertical aline- Ioo ment with the latter cylinder is the cylinde'.- C of the fuel-pump, whose piston C2 is directlyv connected to the piston B2 ofcylinder B by means of its vertical piston-rod c, the latter forming, preferably, an extension of the piston-rod b. l

D is a reservoir for compressed air, connected to the air-compressing side of cylinder B and adapted to receive and store the surplus of air compressed in cylinder B over and above whatis necessary for` the regular charges .supplied to the cylinder U, as will be more fully hereinafter described.

Communication between the cylinders U and B and between the expansion side of the latter cylinder and the atmosphere and also between the air-reservoir D and the cylinder U is controlled by a single horizontally-sliding valve V, reciprocating in a closed box or cham ber V3. The downwardly and laterally extended lower head of cylinder U has a port o leading from an annular space o4 to the valve-chamber V3, another similar port o' leading from the valve-chamber V3 to the upper end of cylinder B, and a third port 02 extending at right angles to ports o and o' from valve-chamber V2 to the atmosphere. The sliding valve Vhasareeess or pocket q formed in its upper face wide enough to span the faces of the ports 0 and 0' or o and o2 and has also a straight vertical port q formed directly through it at one side of the recess q. Ou the lower face of valve V is a spring-supported cut-oiislide V,whose function is to control the Vamount of compressed air admitted to cylinder U through the port q of the valve V in the manner hereinafter explained. The cut-off slide V is carried by and reciprocates with the valve V; but the limit of its movement to the left, Fig. 2, is determined by an adjustable stop e2, while its movement to the right is limited by a stop e, controlled by a governor E through a bell-crank lever e. The valve V and its cut-off slide V are positively actuated in both directions from shaft G hy an eccentric g, eccentric-rod g', bell-crank lever g2, and valve-stein g3, all as plainly shown in Fig. 2.

'lhe fuel-inlet pipe of the fuel-pump O is designated by i and is provided with a throttle-valve o7, automatically operated, as hereinafter described. vThe fuel inlet and discharge valves are shown at o2 and rs, respeclively, and o is a valve for admitting air, if desired, so that the pump may furnish fuel alone or an incombustible mixture of fuel and air (as equal parts of each) tothe combustioncylinder U. The fuel is forced from the pump C through a pipe C3 and inlet-valve V2 to the annular space o4 in the lower head of cylinder U, where it meets and mingles with the com pressed air admitted to said ann ular space through valve V.

A short pipe p, provided with a stop-cock o9, connects the air-compressing end of cylinder B with the reservoir D, the end of said pipe entering the reservoir being provided with a check-valve yv2 to prevent air within the pipe p and its connections from entering the reservoir. The pipe p' is tapped bya verl tical pipe p', and this latter is in turn tapped by a horizontal pipe p2, havinga stop-cock v10 and leading into the valve-chamber V3. (See dotted lines in Fig. l.) The upper end of pipe p' taps a short pipe p3, one end of which communicates with a diaphragm F (constituting a pressure-regulating device) and the other with a valve-chamber o, containing a slidingpiston-valve o, located above thereservoir D and connected with the latter by a short pipe @'12, equipped with a stop-cock tis. Pivoted to a lug on cylinder C is a lever K, which rests near its pivoted end on the stem of the diaphragm F and at its outer end is connected to the stem of the piston-valve c5, it being also connected at a point intermediate its ends with the stem of the throttlevalve r.

H, Fig. 2, represents a Way-shaft suitably journaled in brackets secured to the engineframe and driven from a pulley on the main shaft Gbya belt tl. This way-shaft through suitable bevel-gearing, as shown, operates the governor E and through it the variable stop e'. A second way-shaft I, journaled above and operated from way-shaft H by a belt h3, carries a cam h2, which through bell-crank lever 7L operates the inlet-valve V2 at the proper time to admit a fresh charge of fuel to the annular space 04. Y

The igniter (diagrammatically indicated at n) may be of any approved type operated from a moving part of the engine to tire the successive charges at the proper times.

The operation of the engine is as follows: The pistons A and B2 being connected to the driving-shaft G on cranks set one hundred and eighty degrees apart, when the piston A' is performing its downward or working stroke the piston B2 is moving upward, expelling the expanded gas from above it through ports o'Y o2 and recess q in valve V (the latter valve occupying the position shown in Fig. 2) and drawing in air beneath it through valve fu. At or about the completion of this stroke of pistons A' and B2 the valve V is shifted so as to bring cylinders U and B into communication through ports o o and recess q in valve V. During the upward stroke of piston A' and the simultaneous downward stroke of piston B2, therefore, the burning and expanding gases in cylinder U are passing into the cylinder B (which in practice willbe made larger in diameter than cylinder U, as usual in compound engines) and exerting pressure on the upper face ot' piston B2, having on their way imparted a portion of their heat to the regenerator in cylinder U. At the same time the air below the piston B2 is compressed and discharged through valve fu' into the pipes p p'p2p2 and valve-chamber V3 and fuel enters the pump C through valve Ivand air also through the valve o4, (where this valve is employed.) At or about the completion of the upward stroke of piston A and the downward stroke of piston B2 the valve V is again IOC) IIO

shifted by eccentric g to the position shown in Fig. 2. This shuts ed communication between cylinders U and B, opens cylinder B to the exhaust, and permits the air previously compressed in pipesppp2p3 andv valvechamber V3 to rush through ports q' and o into the annular space 04. Simultaneously (or substantially so) with the admission of the compressed air to the annular space o4 the fuel-inlet valve V2 is actuated by its cam h2 to admit a charge of fuel, previously compressed into the pipe C3 bythe fuel-pump C, into said annular space o4, where it meets and commingles with the compressed air in such proportions as to form therewith a combustible mixture, the said mixture passing thence through the regenerator (where it is preparatorily heated) into the upperend of the combustion-cylinder U, where it is tired by the igniter n just after the piston A has begun its downward stroke. The above-described cycle of operations is thereupon repeated.

The fuel-inlet valve V2 is open only during a short while-approximately during a quarter of a revolution-and it should close before the air-supply port o is closed in order to blow all the fuel out of the regenerator into the combustion-chamber. The closing of the port o for the compressed-air supply depends upon the action of the governor E, controlling the cut-off slide V of the main valve V. By leading the compressed air and fuel forming the constituents of each charge into the combustion-chamber by way of the annular space oAL the lubricated parts of the cylinder and piston are, in a large measure, protected against heat.

Whenever the pump B compresses air in excess of that required for the combustible charges supplied to the cylinder U, the airpressure in pipes p, p, p2, and p3 rises and,

acting on diaphragm F through lever K and the stem of piston-valve 06, raises the latter valve and allows the compressed air to escape through stop-cock fuwhich is ordinarily open, into the reservoir D, at the same time throttling the fuel-supply by valve c7, and thus causing the engine to slow down. This compressed air may be subsequently utilized to assist in the operation of starting the engine in the following manner; The fly-wheel will be turned by hand until the piston A of the combustion-cylinder U has been brought to the upper end of its stroke and just past the dead-center, at which point the valve V will be brought to the position shown in Fig. 2. Then by opening stop-cock 'v9 in pipe j) compressed air in reservoir D will rush through pipes p 19'192 and valve V into the upper end of cylinder' U and expanding against the piston A impel the latter on its downward stroke and start the operation of the engine.

It will be noticed that the valve@1G is a balanced piston-valve, both the pressure in the reservoir D and that in the pipes 1;,12, p2, and p3 acting on the opposite ends of said valve equally, so that nothing but excess of pressure on the diaphragm F will effect the movement of said valve so as to admit compressed air to the reservoir D.

Having thus described my invention and illustrated my preferred means for carrying the same into effect, what l claim as new, and desire to secure by Letters Patent, is-

l. In an internal-combustion engine, the combination with the combustion-cylinder provided with a regenerator, and means for supplying fuel under pressure to said cylinder, of a combined low-pressure expansioncylinder and air-compressor, and a single valve located intermediate said combustion and expansion cylinders, and controlling the admission of compressed air to said combustion-cylinder, the transfer of the products of combustion from the latter to the expansioncylinder, and the exhaust from the latter to 'the atmosphere, substantially as described.

2. In an internal-combustion engine, the combination with the combustion-cylinder provided with a regenerator, and means for supplying fuel under pressure to said cylinder, of a combined low-pressure expansioncylinder and air-compressor, a single valve located intermediate said combustion and expansion cylinders, and controlling the admission of compressed air to said combustion-cylinder, the transfer of the products of combustion from the latter to the expansion-cylinder, and the exhaust from the latter to the atmosphere, and a governor-controlled de- Vice on said valve for regulating the amount of compressed air supplied to the combustion-cylinder, substantially as described.

3. In an internal-combustion engine, the combination with the high-pressure combustion-cylinder, the low-pressure expansion-cylinder, the fuel-pump and air-compressor, all connected to a common crank-shaft and having suitable Valve-controlled connections, of an air-reservoir communicating with the delivery side of the air-compressor through a suitable valve-controlled connection, a pressure-regulating device automatically governing the admission of surplus compressed air to the reservoir through said Valve-controlled connection, and means for admitting com- IOO IIO

pressed air from the reservoir to the combustion-cylinder to effect the starting of the engine, substantially as described.

4. In an internal-combustion engine, the combination with the high-pressure combustion-cylinder, the low-pressure expansion-cylinder, the fuel-pump and air-compressor, all connected to a common crank-shaft and having suitable valve-controlled connections, of an air-reservoir communicating with the delivery side of the air-compressor through a suitable valve-controlled connection, a pressure-regulating device automatically governing the admission of surplus compressed air to the reservoir through said Valve-controlled connection, a throttle-Valve in the fuel-ad-v mission pipe also operated by said pressureregulating device, and means for admitting compressed air from the reservoir to the combustion-cylinder to eect the starting of the engine, all substantially as described.

5. In an internal-combustion engine, the combination with ahigh-pressure combustioncylinder provided with a regenerator, and having its piston connected to the crank-shaft of the engine, of a low-pressure and 10W-tem- 'perature expansion-cylinder, an air-compressor, and a fuel-pump, all three arranged in alinement and having their pistons connected to the crank-shaft through a common pistonrod and pitman at a point opposite the connection of the piston of the combustion-cylinder with said shaft, and suitable valve-con trolled connections between the combustioncylinder and the expansion-cylinder, the aircompressor and the fuel-pump respectively, substantially as and for the purpose described.

6. In an internal-combustion engine, the combination with a highpressure combustioncylinder provided with a regenerator, and having its piston connected to the crank-shaft of the engine, of a low-pressure and low-temperature expansion-cylinder, an air-compressor, and a fuel-pump, all three arranged in alinement and having their pistons connected to the crank-shaft through a common pistonrod and pitman at a point opposite the connection of the piston of the combustion-cylinder with said shaft, suitable valve-controlled connections between the combustioncylinder and the expansion-cylinder, the air' compressor and the fuel-pump respectively, and an air-reservoir connected with the aircompressor to receive the surplus of the compressed air over that required by the combustion-cylinder, substantially as and for the purpose described.

HENNING F. WALLMANN.

/Vitnesses:

W. W. DONLEY, C. C. WITT. 

